PLEASE HELPPPP!!!
diameter & volume question

Answer:

The correct answer is

C. 6 Protons

Explanation:

Carbon is a nonmetallic element that is available in  both organic and inorganic compounds.

    Carbon belongs to group 14 elements in the periodic table,carbon is a chemical element with the symbol C and atomic number 6, it can  form long chains with its own atoms, a feature called catenation.

Two allotropes of carbon available are diamonds and graphites, which have different crystalline structures

The physical properties of carbon vary widely with the allotropic form.

examples are.

Answer:

6.941 grams

Explanation:

The molecular formula for Lithium is Li. The Si base unit for amount of substance is mole. 1 mole is equal to 1 moles Lithium, or 6.941 grams

Answer:

9.647989999999998

Explanation:

Answer: Provided in the explanation section

Explanation:

Our questions says that:

It is usually assumed that an action potential begins immediately at the cathode. If this were true, both methods for calculating conduction velocity would provide the same answer. However, when a strong stimulus intensity is used, the action potential may begin some distance away from the cathode. Under these conditions, the difference method would be more accurate.Did you observe any important difference between the conduction velocity values?

Answer to this :

By using the difference method, you subtract out any "uncertainties" involved in the measurement of latencies. Say for example, saw we are uncertain as to where the AP's are actually originating within the vicinity of the stimulating electrodes, this "error" will be introduced into both latency measurements, and therefore subtracted out when performing a difference method calculation.

However, the difference method is only experimentally sound when one is dealing with the same population of nerve fibres over the recording electrodes used, which is not the case with the sciatic nerve, as it is a short nerve, and thin at one end.

    The non-uniformity of the nerve, and the difficulty in making accurate measurements of very small distances and latencies are principal points to consider when making conduction velocity measurements. Naturally if the nerve studied were longer and more uniform, we would improve the accuracy of our calculations.

cheers i hope this helped !!!!

Answer:

q = - 3.569KJ 0r 3.569KJ Liberated heat (signifying the change in heat is negative)

Explanation:

liberated heat implies that change in heat is negative , therefore

q = -m c ΔT

where, m = mass of the Silver = 249 g

c = specific heat capacity of Silver = 0.235 Jg^{-1} °C^{-1

 ΔT = change in temperature = 87°C- 26 °C= 61°C

q = -m x c x ΔT

= - 249 x 0.235 x 61 = - 3569.415J  rounded to -3569J

Changing to KJ becomes= -3569/1000= - 3.569 KJ

q = - 3.569KJ 0r 3.569KJ liberated heat.

Explanation:

Boiling-point elevation describes the phenomenon that the boiling point of a liquid (a solvent) will be higher when another compound is added, meaning that a solution has a higher boiling point than a pure solvent. This happens whenever a non-volatile solute, such as a salt, is added to a pure solvent, such as water.

Hope it was helpful

Explanation:

First off, the + 1 charge means that the metal has lost an electron.

To identify the metal, we have to know the total number of electrons in the 3d sub shell.

Total number of electrons = 1 + 10 = 11

This metal belongs to the fourth period in the periodic table (that's where transition metals begin to occur).

This means that the 11th metal in this period is the metal. That happends to be Copper.

Answer:

a) First-order.

b) 0.013 min⁻¹

c) 53.3 min.

d) 0.0142M

Explanation:

Hello,

In this case, on the attached document, we can notice the corresponding plot for each possible order of reaction. Thus, we should remember that in zeroth-order we plot the concentration of the reactant (SO2Cl2 ) versus the time, in first-order the natural logarithm of the concentration of the reactant (SO2Cl2 ) versus the time and in second-order reactions the inverse of the concentration of the reactant (SO2Cl2 ) versus the time.

a) In such a way, we realize the best fit is exhibited by the first-order model which shows a straight line (R=1) which has a slope of -0.0013 and an intercept of -2.3025 (natural logarithm of 0.1 which corresponds to the initial concentration). Therefore, the reaction has a first-order kinetics.

b) Since the slope is -0.0013 (take two random values), the rate constant is 0.013 min⁻¹:

[tex]m=\frac{ln(0.0768)-ln(0.0876)}{200min-100min} =-0.0013min^{-1}[/tex]

c) Half life for first-order kinetics is computed by:

[tex]t_{1/2}=\frac{ln(2)}{k}=\frac{ln(2)}{0.013min^{-1}} =53.3min[/tex]

d) Here, we compute the concentration via the integrated rate law once 1500 minutes have passed:

[tex]C=C_0exp(-kt)=0.1Mexp(-0.013min^{-1}*1500min)\\\\C=0.0142M[/tex]

Best regards.

Answer:

[tex]Purity=99\%[/tex]

Explanation:

Hello,

In this case, the undergoing precipitation reaction is:

[tex]MgCl_2+2AgNO_3\rightarrow Mg(NO_3)_2+2AgCl[/tex]

Thus, for the 0.2500 moles of silver nitrate, the following mass of magnesium chloride is consumed (consider their 2:1 molar ratio):

[tex]m_{MgCl_2}=0.2500molAgNO_3*\frac{1molMgCl_2}{2molAgNO_3} *\frac{95.2gMgCl_2}{1molMgCl_2} \\\\m_{MgCl_2}=11.90gMgCl_2[/tex]

Therefore, the purity of the sample is:

[tex]Purity=\frac{11.90g}{12.00g}*100\%\\ \\Purity=99\%[/tex]

Best regards.

Answer: 99. 17%

Explanation:

MgCl2(aq)+2AgNO3(aq)⟶2AgCl(s)+Mg(NO3)2(aq)

(0.2500 mol AgNO3 × 1 mol (MgCl2) /2 mol (AgNO3) × 95.211 g MgCl2 /1 mol MgCl2)

divided by 12.00 g sample = 0.99178 X 100 ≈ 99.18%

Answer:

Option f: an addition of HCl will exceed the buffer capacity. The option d is also correct since it is a consequence of the option f.

Explanation:

The pH of the buffer solution before the addition of HCl is:

[tex]pH = pKa + log(\frac{[KF]}{[HF]})[/tex]

[tex]pH = -log(6.8 \cdot 10^{-4}) + log(\frac{0.371}{0.494}) = 3.04[/tex]  

The hydrochloric acid added will react with the potassium fluoride as follows:

H₃O⁺(aq)  +  F⁻(aq) ⇄   HF(aq) + H₂O(l)

The number of moles (η) of potassium fluoride (KF) and the HF before the addition of HCl is:

[tex] \eta_{KF}_{i} = C_{KF}*V = 0.371 M*1 L = 0.371 mol [/tex]

[tex] \eta_{HF}_{i} = C_{HF}*V = 0.494 M*1 L = 0.494 moles [/tex]

The number of moles of the HCl added is 0.408 moles. Since the number of moles of HCl is bigger thant the number of moles of KF, the moles of HCl that remains after the reaction is:

[tex] \eta_{HCl} = \eta_{HCl} - \eta_{KF}_{i} = 0.408 moles - 0.371 moles = 0.037 moles [/tex]  

Hence, the KF is totally consumed after the reaction with HCl and thus, exceding the buffer capacity.  

We can calculate the pH after the addition of HCl:

HF(aq) + H₂O(l) ⇄ F⁻(aq) + H₃O⁺(aq)    (1)

The number of moles of HF after the reaction of KF with HCl is:

[tex] \eta_{HF} = 0.494 moles + (0.408 moles - 0.371 moles) = 0.531 moles [/tex]

And the concentration of HF after the reaction of KF with HCl is is:

[tex] C_{HF} = \frac{\eta_{HF}}{V} = \frac{0.531 moles}{1 L} = 0.531 moles/L [/tex]

Now, from the equilibrium of equation (1) we have:

[tex] Ka = \frac{[H_{3}O^{+}][F^{-}]}{[HF]} [/tex]

[tex] Ka = \frac{x^{2}}{0.531 - x} [/tex]  (2)

By solving equation (2) for x we have:

x = 0.0187

Finally, the pH after the addition of HCl is:

[tex] pH = -log (H_{3}O^{+}) = -log (0.0187) = 1.73 [/tex]

Therefore, the addition of HCl will exceed the buffer capacity and thus, lower the pH by several units. The correct option is f: an addition of HCl will exceed the buffer capacity. The option d is also correct since it is a consequence of the option f.

I hope it helps you!

Answer:

Hey mate,

Here is your answer. Hope it helps you

Explanation:

Primary alcohols are those alcohols where the carbon atom of the hydroxyl group(OH) is attached to only one single alkyl group. Some of the examples of these primary alcohols include Methanol (, propanol, ethanol, etc. The complexity of this alkyl chain is unrelated to the classification of any alcohol considered as primary. The existence of only one linkage among –OH group and an alkyl group and the thing that qualifies any alcohol as a primary.

Answer:

14 moles

Explanation:

For an Ideal gas,

PV = nRT...................... Equation 1

Where P = Pressure, V = Volume, n = number of mole, R = Molar gas constant.

make n the subject of the equation

n = PV/RT.................. Equation 2

Given: P = 14.297 atm, V = 22.9 L = 22.9 dm³, T = 12 °C = (12+273) K = 285 K.

Constant: R = 0.082 atm.dm³/K.mol

Substitute these values into equation 2

n = (14.297×22.9)/(285×0.082)

n = 327.4013/23.37

n = 14.009

n ≈ 14 moles

The correct answer is B. A homogeneous mixture has the same properties for every part of the mixture, so the quality of the material is consistent.

Explanation:

In a homogenous mixture, all the components are equally integrated; this means the final result in the case of a material is a material that looks uniform and also has the same properties in every part of section. This homogeneity and consistency are especially important if you are testing the properties of the material or using it for a specific application because if you use a homogenous mixture the quality and properties will be consistent and thus you can obtain consistent results.

Answer: B. It exposes more of the solute to the water molecules.

Explanation:

Rate of a reaction is dependent on following factors:

a) adding a catalyst: Adding a catalyst increases the rate of reaction

b) reducing the surface area: The rate of the reaction will decrease by reducing the surface area

c) raising the temperature: Increasing the temperature increases the rate of the reaction.

d) increasing the amount of reactants : Increasing the amount of reactants increases the rate of reaction.

If the reactants are present in smaller size, more reactants can react as decreasing the size increases the surface area of the reactants which will enhance the contact of molecules. Hence, more products will form leading to increased rate of reaction.

Thus reducing solute particle size increase the speed at which the solute dissolves in water by exposing more of the solute to the water molecules.

Answer:

B. It exposes more of the solute to the water molecules.

Answer:

THE SPECIFIC HEAT CAPACITY OF THE ALUMINIUM CAN IS 0.03747 J/g K

Explanation:

Heat liberated (Q) = MCΔT

Heat = 106.8 J

M = mass = 10 g

ΔT = 12°C= 12 + 273 K = 285 K

C = specific heat capacity = unknown

At a rise in 12 °C temperature, the aluminium can possesses a specific heat capacity of =

C = Q / MΔT

C = 106.8 J / 10 g * 285 K

C = 106.8 J / 2850 g K

C = 0.03747 J/g K

The specific heat capacity of the aluminum can weighing 10 g and absorbs 106.8 J of heat after been warmed to 12°C is 0.03747 J/ g K

Answer:

The specific heat of the aluminium can is 0.89 J/g°C

Explanation:

Step 1: Data given

Mass of the aluminium can = 10.0 grams

The amount of energy absorbed = 106.8 J

The temperature rises 12.0 °C

Step 2: Calculate the specific heat of the aluminium can

Q = m*c* ΔT

⇒with Q = the heat absorbed = 106.8 J

⇒with m = the mass of the aluminium can = 10.0 grams

⇒with c = the specific heat of the aluminium can = TO BE DETERMINED

⇒with ΔT = the rise of the temperature = 1.0°C

106.8 J = 10.0 grams * C * 12.0 °C

C = 106.8 J / (10.0 grams * 12.0 °C)

C = 0.89 J/g°C

The specific heat of the aluminium can is 0.89 J/g°C

Answer:

[tex]K=3.2[/tex]

Explanation:

Hello,

In this case, for the given equilibrium, we write the law of mass action:

[tex]K=\frac{[PCl_3][Cl_2]}{[PCl_5]}[/tex]

Next, in terms of the change [tex]x[/tex] due to the reaction extent (ICE procedure):

[tex]K=\frac{x*x}{1M-x}[/tex]

Clearly, the initial concentration phosphorous pentachloride is 1 M (one mole per litre), therefore, since the equilibrium concentration is 0.2 M (same volume) we can compute [tex]x[/tex]:

[tex]x=1M-0.2M=0.8M[/tex]

Thus, we compute the equilibrium constant:

[tex]K=\frac{0.8*0.8}{0.2} \\\\K=3.2[/tex]

Regards.

Answer:

63.45g of I₂ can be produced

Explanation:

IF₅ reacts with IF to produce IF₇ and I₂. The reaction is:

IF₅ + 2 IF → IF₇ + I₂

Moles of 10.0g of IF₅ (221.89g/mol):

10.0g IF₅ × (1mol / 221.89g) = 0.0451 moles of IF₅

Using PV / RT = n, it is possible to find moles of 11.20L of IF, thus:

1atm×11.20L / 0.082atmL/molK × 273K = 0.500 moles of IF.

At STP, pressure is 1atm, temperature is 273K and gas constant R is 0.082atmL/molK

For a complete reaction of IF₅ you need:

0.0451 moles of IF₅ × (2 moles IF / 1 mole IF₅) = 0.902 moles of IF. As you have just 0.500 moles of IF, the IF is the limiting reactant.

2 moles of IF produce 1 mole of I₂. 0.500 moles of IF produce:

0.500mol IF ₓ ( 1 mol I₂ / 2 mol IF) = 0.250 mol I₂

As molar mass of I₂ is 253.81g/mol, mass of 0.250 mol I₂ are:

0.250mol I₂ ₓ (253.81g / mol) =

Answer:

1. Methyl ethanoate i.e CH3COOCH3

2. Methyl butanoate i.e CH3CH2CH2COOCH3

Explanation:

The reaction between an organic acid and alcohol is called esterification in which an ester is formed along side with water.

Thus, the name ester formed can be obtained as follow:

1. Reaction of acetic acid, CH3COOH with methanol, CH3OH.

CH3COOH + HOCH3 –> CH3COOCH3 + H2O

The name of the ester formed is methyl ethanoate i.e CH3COOCH3

2. Reaction of butanoic acid, CH3CH2CH2COOH with methanol, CH3OH.

CH3CH2CH2COOH + HOCH3 —> CH3CH2CH2COOCH3 + H2O

The name of the ester formed is methyl butanoate i.e CH3CH2CH2COOCH3

Answer:

I, II, and III

Explanation:

In the titration of NH₃ with HCl:

NH₃ + HCl → NH₄⁺ + Cl⁻

Where NH₃ is the weak base and NH₄⁺ is the conjugate acid.

I: At 0 L HCl, pH would be calculated based on the concentration and Kb of the weak base: At 0L of HCl, you will have just NH₃ in solution. That means you would calculate the pH just from the concentration of the weak base using Kb. That means I is true.

II: At 1 L HCl, pH would be calculated based on the concentration and Ka of the conjugate acid: When you add 1L of HCl, you will have in solution just NH₄⁺, the conjugate acid. That means you would calculate the pH of the solution just with the Ka of the conjugate acid and its concentration. II is true.

III: At 2 L HCl, pH would be calculated based on the concentration of excess acid in solution: At 2L of HCl solution, you have HCl in excess in the solution. As HCl is a strong acid, the pH would be affected in the big way by this concentration in excess. III is true.

Answer:it has fixed quantity

Explanation:energy between chemical bonds is hard to measure

Answer:

It has a fixed quantity.

Explanation:

Answer:

The +3 oxidation state is characteristic of the actinides.

All actinides are radioactive.

Cerium (Ce) rnakes 100th in abundance (by mass %).

The actinides are silvery and chemically reactive.

In the periodic table,the The +3 oxidation state is characteristic of the actinides. All actinides are radioactive.The actinides are silvery and chemically reactive.

Periodic table is a tabular arrangement of elements in the form of a table. In the periodic table, elements are arranged according to the modern periodic law which states that the properties of elements are a periodic function of their atomic numbers.

It is called as periodic because properties repeat after regular intervals of atomic numbers . It is a tabular arrangement consisting of seven horizontal rows called periods and eighteen vertical columns called groups.

Elements present in the same group have same number of valence electrons and hence have similar properties while elements present in the same period show gradual variation in properties due to addition of one electron for each successive element in a period.

Learn more about periodic table,here:

https://brainly.com/question/11155928

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Answer:

2.05*10⁻⁵ moles of CF₂ can dissolve in 100 g of water.

12.82 moles of CaF₂ will dissolve in exactly 1.00 L of solution

Explanation:

First, by definition of solubility, in 100 g of water there are 0.0016 g of CaF₂. So, to know how many moles are 0.0016 g, you must know the molar mass of the compound. For that you know:

So the molar mass of CaF₂ is:

CaF₂= 40 g/mole + 2*19 g/mole= 78 g/mole

Now you can apply the following rule of three: if there are 78 grams of CaF₂ in 1 mole, in 0.0016 grams of the compound how many moles are there?

[tex]moles=\frac{0.0016 grams*1 mole}{78 grams}[/tex]

moles=2.05*10⁻⁵

2.05*10⁻⁵ moles of CF₂ can dissolve in 100 g of water.

Now, to answer the following question, you can apply the following rule of three: if by definition of density in 1 mL there is 1 g of CaF₂, in 1000 mL (where 1L = 1000mL) how much mass of the compound is there?

[tex]mass of CaF_{2}=\frac{1000 mL*1g}{1mL}[/tex]

mass of CaF₂= 1000 g

Now you can apply the following rule of three: if there are 78 grams of CaF₂ in 1 mole, in 1000 grams of the compound how many moles are there?

[tex]moles=\frac{1000 grams*1 mole}{78 grams}[/tex]

moles=12.82

12.82 moles of CaF₂ will dissolve in exactly 1.00 L of solution

Answer:

D

Explanation:

From given choices it is D.

Answer:

matter, dense, equal

Explanation:

According to Rutherford's nuclear theory, the core of an atom (nucleus) contains most of the matter of an atom and is dense, so the majority of the mass of a fluorine atom cannot be due to its nine electrons. According to Rutherford's nuclear theory, most of the volume of an atom is empty space, so the volume of a hydrogen atom cannot be mostly due to the proton. According to Rutherford's nuclear theory, the number of negatively charged particles outside the nucleus is equal the number of positively charged particles within the nucleus, so a nitrogen atom has 7 protons and 7 electrons, while a phosphorous atom cannot have 15 protons and 150 electrons.

Answer:

The value of Kc C. remains the same.

The value of Qc C. is less than Kc.

The reaction must: A. run in the forward direction to reestablish equilibrium

The number of moles of Cl2 will  B. decrease.

Explanation:

Le Chatelier's Principle states that if a system in equilibrium undergoes a change in conditions, it will move to a new position in order to counteract the effect that disturbed it and recover the state of equilibrium.

A decrease in volume causes the system to evolve in the direction in which there is less volume, that is, where the number of gaseous moles is less.

But temperature is the only variable that, in addition to influencing equilibrium, modifies the value of the constant Kc. So if the volume of the equilibrium system is suddenly decreased at constant temperature: The value of Kc remains the same.

As mentioned, if the volume of an equilibrium gas system decreases, the system moves to where there are fewer moles. In this case, being:

PCl₃(g) + Cl₂(g) ⇔ PCl₅(g)

The equilibrium in this case then shifts to the right because there is 1 mole in the term on the right, compared to the two moles on the left. So, The reaction must: A. run in the forward direction to reestablish equilibrium.

By decreasing the volume, and so that Kc remains constant, being:

[tex]Kc=\frac{[PCl_{5} ]}{[PCl_{3}]*[Cl_{2} ]}=\frac{\frac{nPCl_{5} }{Volume} }{\frac{nPCl_{3}}{Volume}*\frac{nCl_{2} }{Volume} } =\frac{nPCl_{5}}{nPCl_{3}*nCl_{2}} *Volume[/tex]

 where nPCl₅, nPCl₃ and nCl₂ are the moles in equilibrium of PCl₅, PCl₃ and Cl₂

so,  the number of moles of Cl₂ should decrease.The number of moles of Cl2 will  B. decrease.

If the reaction quotient is less than the equilibrium constant, Qc <Kc, the system will evolve to the right, the direct reaction prevailing, to increase the concentration of products. So in this case, if the reaction moves to the right, the value of Qc C. is less than Kc.

Answer:

Calcium

Explanation:

Since the element reacts with oxygen to form an oxide with the formula MO, the charge on the element is +2.

Also, since the oxide MO when dissolved in water is basic, the metal is an alkali earth metal.

From the above conditions;

The metal is not arsenic because arsenic is a metalloid has the  following oxides As₂O₃ and As₃O₅ and are respectively amphoteric and acidic in nature

The metal is not germanium because is a metalloid and even though germanium oxide has the formula GeO₂, it is amphoteric.

The metal is not chlorine because chlorine is a non-metal

The metal is definitely calcium because calcium oxide has the formula CaO and calcium is an alkaline earth metal.

The metal is not selenium because selenium is anon-meal and its oxide has the formula Se0₂ and is acidic

Answer:

See explanation below

Explanation:

You are missing certain data. I found one, in the attached picture. All you have to do is replace your data in this procedure to get an accurate answer.

According to the picture attached, we have 2.4 g of HBr and 1.9 g of NaOH. This mix produces 0.411 g of water. To get the %yield of water, we first need to see how many theorical grams of water are formed. With this we can calculate the %yield.

The overall reaction is:

HBr + NaOH --------> NaBr + H₂O

We have a mole ratio of 1:1 so, let's see which is the limiting reactant between the acid and the base, using the reported molar mass for each (MM HBr = 80.9119 g/mol; MM NaOH = 39.997 g/mol)

moles HBr = 2.4 / 80.9119 = 0.02966 moles

moles NaOH = 1.9 / 39.997 = 0.0475 moles

So, we can clearly see that the moles of NaOH are in excess, so the HBr is the limiting reactant.

As we have a mole ratio of 1:1 with each compound here, and that the HBr is the limiting reactant we can say that:

moles HBr = moles H₂O = 0.02966 moles of water

Now, using the molar mass of water, let's calculate the theorical yield of water: (MM water = 18.01528 g/mol

m H₂O = 0.02966 * 18.01528 = 0.534 g

We have the theorical yield, let's calculate the % yield:

% = 0.411 / 0.534 * 100

% = 76.92%

Answer:

D.

Explanation:

Water is polar, for one thing. Polar mixes with polar, nonpolar mixes wih nonpolar. This leaves D.

Answer:

A) 2.41 * 10^-2 M

Explanation:

Here we go from grams of percipitate to moles of Silver nitrate because we already know NaCl is excess so we don't care about that.

[tex]0.148gAgCl * \frac{1mol AgCl}{143.32 g AgCl} * \frac{1 mol AgNO3}{1 mol AgCl}\\ = 0.00103 mol AgNO3[/tex]

Now that we have moles we know molarity is moles/litres so we just plug it in:

Molarity = mol/litres = 0.00103/0.0428 L = 0.0241 M or 2.41 * 10^-2 M

Answer:

15g

Explanation:

Molar mass of acetic acid = 60g/mol

Molarity = mass ÷ molar mass

mass = 0.25 × 60

= 15g

∴ 15g of acetic acid weighed into 1L volumetric flask would give 0.25M  of acetic acid.

Alternatively, if the solution is being prepared from a stock solution of known concentration, (say 500mL of 0.5M solution), the formular C2V1 =C2V2 can be used to find the dilution volume.

Answer:

I think it's D. 300(g) + Fe2O3(s)